1. Field
One or more embodiments described herein relate to a display device with a touch panel and a method for converting the driving frequency of a touch panel.
2. Description of the Related Art
A variety of flat panel displays have been developed. Examples include liquid crystal displays, organic light emitting diode (OLED) displays, and electrophoretic displays. Each of these displays generates an image using an electro-optical active layer. A liquid crystal display uses a liquid crystal layer as an electro-optical active layer. An OLED display uses an organic emission layer as an electro-optical active layer. An electrophoretic display uses an active layer including charged particles. In these displays, a field-generating electrode is connected to a switching element (e.g., a thin film transistor) which receives a data signal. The active layer converts the data signal to an optical signal for displaying an image.
These or other types of displays may perform a touch sensing function based on user interaction. The touch sensing function may be performed to determine contact information (e.g., whether an object contacts a screen, the position of the contact, etc.). The contact information may be determined by sensing a change in pressure, charges, light, or other conditions, on a display screen. This may occur, for example, when a user writes text or draws a figure by contacting the screen with a finger or a touch pen. The display may receive an image signal based on the contact information.
The touch sensing function may be implemented by a sensor. The sensor may be, for example, a resistive type, capacitive type, electro-magnetic (EM) type, or optical type of sensor. The capacitive-type sensor includes a sensing capacitor which may included, for example, a sensing electrode for transferring the sensing signal. This sensor may determine contact, a contact position, and the like, by sensing a change in the capacitance of the sensing capacitor when an object (e.g., a finger or stylus) approaches and contacts the sensor. However, in the capacitive-type sensor, there is a problem in that a user touch may not be sensed because of display noise and/or external noise.